By using a user password set in UserPassword. In this mode, external viewers such as Adobe Acrobat will ask the user for the same password when opening the file for viewing. If the correct password is supplied, then all operations and rights are granted.

By using an owner password set in OwnerPassword. In this mode, external viewers such as Adobe Acrobat will ask the user for the same password when opening the file for viewing. If the correct password is supplied, the editor will check the various access rights properties to allow or disallow certain operations on the PDF file such as printing or editing.